Crossword puzzle

SOMEONE PLEASE HELP ME!!!

Which group of chordates does  notpossess true backbones?                 a.  birds      b.  frogs and toads      c.  lampreys      d.  crocodilians

Which statement best describes a typical difference that could be found between the "analysis" and "conclusion" sections of a lab report? a) only the "conclusion" describes errors that occurred during the experiment, and only the "analysis" section suggests further research.b) only the "analysis" section includes specific data comparisons, and only the "conclusion" section suggests further research.c) only the "analysis" section discusses whether the original hypothesis was supported, and both sections include graphs of data.d) only the "conclusion section discusses whether the original hypothesis was supported, and both sections suggest further research.(the answer is b i just took the test)

Drag each tile to the correct box. the body monitors the levels of oxygen in the blood to regulate breathing. isabel is running in a marathon and is near the finish line. she feels out of breath. how will her nervous system work to generate a reaction? arrange the tiles in chronological order. isabel's breathing rate increases. sensory receptors in the arteries detect low oxygen levels. the brain sends signals through motor neurons. sensory neurons generate an impulse. the central nervous system relays an impulse to certain brain regions.